1. Field of the Invention
The present invention relates to improved endoprostheses for treating disease of the vasculature.
2. Discussion of the Related Art
Endoprostheses are commonly used for treating disease of the vasculature. By way of example, bifurcated stent grafts may be used in the treatment of abdominal aortic aneurisms, which generally affect the abdominal aorta and may extend down into the iliac arteries. More generally, stents and stent grafts may be used in various indications to reinforce the vasculature and/or otherwise provide an open flow lumen.
Due to the tortuous nature of the vasculature, not only does navigating an endoprosthesis to a treatment site present considerable difficulties, but providing a continuous open flow lumen post deployment through twists and turns in the tortuous vasculature has heretofore been a challenge. In particular, existing stent grafts have a tendency to kink when bent to accommodate a treatment site having a twist or turn, thus closing their lumens to open flow.
Returning to the earlier example, in the treatment of abdominal aortic aneurisms a bifurcated stent graft is often anchored in the abdominal aorta just inferior to the renal arteries and extends down to a bifurcation region and into the iliac arteries. Between the anchors and the bifurcation region, the abdominal aorta may turn up to ninety degrees or more. Existing stent grafts may exhibit kinks at this turn, partially or completely obstructing flow therethrough.
There is thus a need in the art for endoprostheses configured to be deployed around twists and turns in the tortuous vasculature and still maintain open flow lumens.